7/20/2016 8:29 AM
Edited Date/Time: 7/20/2016 8:30 AM
I do like Norco's method of changing the rear center for every size. However, I'd like to see more growth to keep everything in proportion as, in my opinion, the change isn't enough to make the difference I'd want to see.
So...here is the point to this half-baked rant. I've raced bikes for awhile in a number of disciplines. And yes, I ski. For both skiing and road bikes, there are a number of objective ways to determine mount point, ski length, shaping, stem length, frame size, seat position etc. For mountain bikes, we're still sort of using the "guess and check" method to determining what works and what doesn't. This makes some sense being the modern mountain bike rider is far more "dynamic" than that of the static (in one position more or less) road racer.
Put another way, if anyone has had a real road bike fit, you can attest to it being more of a science and less of an art. I'd like to bring this level of objectivity to mountain bike fit and geometry to get more riders on the best tool for the job. For a number of manufacturers, it really wouldn't matter as this level of customization is beyond their reach from a dollar and sense perspective. (though I still say growing the rear center slightly in the longer sizes will create a more balanced bike no matter what). That said, if you could better explain to a rider what sort of numbers to look for in a bike, you could steer them toward better buying decisions. As someone who has tested a lot of bikes, I can promise better fit/geometry will always trump better suspension. (as suspension can always be improved)
I've run formulas to try and figure out how much the rear center should grow in proportion to front center. As a number of people in this thread have noted, its different than skiing for the reason that there are two weighted points on the bike (handlbar and pedal). The proportion to how this is weighted is going to differ person to person and largely be determined by style, arm length, proportions etc. which is likely why some tall dudes may love short stays and some hate them (me).
If this bias between pedal/bar can be better quantified based of body proportions, perhaps we could arrive at a better fit system that goes more in line toward each rider getting on the right rig than simply following "internet trends"(low bars rule! short chainstays are the truth! Long bikes are the best! Slack HT angles rule! Stiff suspension is the best! etc)
Again, as I noted elsewhere in this thread, the ultimate would be some sort of group of sensors on the bike that could actively determine weight bias while riding and objectively explain what tweaks to geometry/suspension setup etc are doing to the the overall ability for the rider to stay in control.
I know, making a lot of leaps here. Its the internet. And this is a forum. Isn't this what its (internet forums) are for?
J